Insecticide



Patented Aug. 8, 1933 oFlf-lca INSECTICIDE, I Eric '1'. Hessle, Lockport, n1., assignor to Mid- West Chemical Company, Chicago, 111.,- a Corporation of Illinois No Drawing.

Serial No. 361,549

1 Claim.

This invention relates to an insecticide derived from aliphatic hydrocarbons.

It is now generally recognized that the insecticidal qualities of hydrocarbon oils are prificipally due to their unsaturated hydrocarbon content and that paraffin hydrocarbons have little if any toxic effect upon insects and pests. Mineral oils high in unsaturated hydrocarbon content, however, are detrimental to plant life 'while' saturated hydrocarbon oils are harmless to plant foliage.

It is therefore an object of, this invention to provide an ,efficient insecticide prepared from a mixture of a product derived largely from unsaturated hydrocarbons and a mineral oil substantially free from unsaturated hydrocarbons.

Other and further important objects of this invention will become apparent from the following description and appended claim.

I have now found that the product produced according to the process described in my U. S. Patent No. 1,830,320 entitled Synthetic tanning materials and a process of making the'same, Serial No. 282,044, filed May 31, v1928-, and comprising largely sulphones and sulphonic acids derived from aliphatic hydrocarbons, possesses very satisfactory insecticidal qualities.

However, this product cannot be used alone as a spray for foliage since it coats the respective parts of a plant with a thin, tight and flexible coating that prevents proper functioning of the plant 1ife. As a result, leaves so sprayed after a shorttime curl and die. When added to a, suitable mineral oil containing'substantially 'no, or very small quantites'of unsaturated hydrocarbons, such as an oil of the white oil type, or an oil that has been oxidized and treated with acid, the product containing sulphones and 5111-; phonic acids derived from aliphatic hydrocarbons proves to be a satisfactory insecticide and at the same time not detrimental .to plant life. The product, comprising an oil mixture of sulphones and sulphonic acid bodies and which will hereinafter be referred to as the'insecticide base,

is prepared in accordance with the process disclosed in my patent referred to above. The

starting material. for the preparation of the insecticide base ispreferably a mineral oil having a high unsaturated hydrocarbon content, most economically one running between 50% and unsaturated content.

Obviously, instead of starting with an oil con taining unsaturated hydrocarbons, the unsaturated hydrocarbons themselves may be used as. starting material. may obtained by.

Application May 8, i929 treating hydrocarbon oils with liquid sulphur dioxide to extract the unsaturated hydrocarbons and then recovering these bodies. In treating a crude mineral oil containing unsaturated hydrocarbons, the oil is first topped to remove the gasoline and distilled from the asphaltic residue in t e usual manner. The kerosene, which does not contain olefines to any extent, may be left in the oil, since it will dissolve the heavier undecomposed hydrocarbons after sulphonation and prevent the formation of emulsions. The oil is thensulphonated at a relatively low temperature, preferably around 0 C., with fuming sulphuric acid, or oleum.

In my preferred methodthe oil is run very slowly through a needle valve into oleum 'containing from 15% to 30% of free $03. Theacid is maintained in a well agitated, cool condition during addition of the oil. Approximately three parts of oleum are used to every four parts by volume of oil. Addition of the oil to the acid takes place over a period of approximately 12- hours, when a sulphonator tr about 900 gallons I capacity is used, after which the sulphonation mass is allowed to stand an additional five hours 30 or so. Upon standing, the mass separates into a bottom layer containing dark acid substances and a top layer composed of the unsulphonated heavy hydrocarbons, such as the parafiins, dissolved in 5 kerosene. I

The top layer is removed by decantation or other method and may be fractionated, after neutralizing and washing, into the various distillates, such as kerosene and others.

The acid layer is run into a large lead-lined tank containing water inan amount sufficient to produce approximately a 30 B. solution after all of the acid syrup has been added. During the addition of the acid, the diluted mass is kept at around room temperature. A separation due to the salting out effect of the sulphuric acid is thus accomplished whereby two layers are formed, the upper comprising a black, gummy, water soluble mass and the lower a water solution of the sulph'uric acid. The purpose of adjusting the den- 1 sity of the diluted solution to approximately 30 B. is to render the sulphonation products substantially insoluble and to obtain the lowest possible concentration of the acid to maintain a 'just suflicient diiierential between the. specific gravity of the acid and that of the black gummy mass, to cause the latter to float upon the acid.

The correct dilution of the mass may be obtained either by first charging the tank with a calculated amount of water or by subsequent dilution after -acid present. I

water.

The lower acid layer is drained and the black, gummy mass, containing approximately 30% of the 30 B. sulphuric acid, is dissolved in water until the organic content (organic dry residue) amounts to approximately 20 to 25% of the diluted mass. The free sulphuric acid content of the diluted mass is then calculated and sufficient alkali added to neutralize all of the free sulphuric acid without neutralizing the organic sulphonic Perhaps the mostsatisfactory method of cal-' culating the free sulphuric'acid in the diluted mass is to take a small aliquot sample from the main batch, neutralize it and precipitate the organic matter with albumen by acidifying with hydrochloric acid. The sample is then filtered and the free sulphuric acid determined upon the filtrate with barium chloride.

, The neutralized, sulphonated products, if desired, are further diluted with water to form a clear, transparent, colloidal water suspension'of any desired concentration. A certain small 'proportion of the total organic matter in this sulphonated product comprises sulphonic acids and the balance, largely sulphones. .The'latter are neither salts nor acids but entirely neutral bodies, which when isolated willbe found to be soluble in ether, chloroform and benzene, but not in water or alcohol. 1

The sulphonic acids in the sulphonated product,'however, are soluble in both water and alcohol and have the peculiar ability of rendering the sulphones water miscible to form clear colloidal suspensions.

Furthermore, the sulphones in this sulphonated product have the property of rendering the products miscible in oil to form a relatively stable emulsion. The sulphonic acid in such an emulsion probably stays in the water solution. Obviously, the sulphonic acids may be neutralized or partially neutralized, if desired. Also the sul- Lphom'c acids may be largely separated from the sulphones and used separately or the'sulphones may be used separately in an oil or water emulsion, or oil and water emulsion, as the insecticide base.

The insecticide base and the mineral oil selected, which is preferably of the white oil type and largely free from unsaturated hydrocarbons, may be mixed in any desired proportions.

When this mixture of insecticide base and mineral oil or a water and oil emulsion of the two, isapplied to plants, the leaves will not be injured and very satisfactory results are obtained from an insecticidal standpoint. It seems probable that a part of the insecticidal value of this preparation is due to the fact that the insecticide base has the property of dissolving greases and thus penetrating the protective layer of grease and wax with which many insects are provided. Furthermore, the sulphones and sulphonic acids of the insecticide base have the property of precipitating gelatinous and albuminous matter, with the result that insects sprayed with this material quickly die.

I am aware that numerous details of the process may be varied through a wide range without departing from the principles of this invention, and I, therefore, do not purpose limiting the patent granted hereon otherwise than necessitated by the prior 'art.

I claim as my invention:

An insecticide composition comprising an emulsion of a non-toxic, substantially saturated, liquid hydrocarbon product and an emulsifying agent in water, said emulsifying agent comprising toxic hydrocarbon sulphones and sulphonic acids.

ERIC T. HESSLE. 

